Internal-combustion engine



O 1 7 April 927 E. R. BURTNETT INTERNAL comsusnou ENGINE;

Filed NOV. 5. 19.25

W 9 5 d x ::H: 8 s

l,623 ,39 l p 1927' E. R. BURTNETT INTERNAL COMBUSTION ENGINE Filed Nov. 5. 1925 2 s t -s t 2 v -E- E I? 1a 1 Patented Apr. 5, 1927.

u it E is a EVERETT R. BURTNETT, 0E nos ANoELEs, cALIEoENIA, Assrorwoarx DIRECT AND MESNE ASSIGNMENTS, To THE AUTOMOTIVE VALVES 00., 0E LOS ANGELES, oALI- FORNIA, A. VOLUNTARY TRUST.

IuTEEE L-coMBUsTIoN ENGIN Application filed November 5,1925. Serial No. 66,963.

My invention relatesgenerally, to internal exhaust, port 14'. Ports13 and 14 are arcombustion engines and more particularly to a two stroke cycle engine power unit that includes a pair of power or combustlon cylinders, charge Volume pumping meansand a piston valve'for controlling the admission of the charge volumes to the pumping means.

The principal objects of my inyention' are to generally improve upon and simpllfy the construction of the existing forms of two stroke cycle internal combustion engines, to provide a power unit wherein the fuel charge volumes are pumped into the com bustion chambers by amember that functions as a compensating reciprocating counterforce to provide a piston, valve for con- I trolling the admission of charge volumes to the'pump, to combine with an engine of the character referred to a counterbalanced crank shaft and to provide connections between the combined pumping piston and counterforce member and the piston valve and the crank shaft whereby said plston valve and pumping piston will function in proper time relation to each other and to the powerpistons in the combustion cylinders that are served by said pumping piston. With the foregoing and other objects in view, my invention consists in certain novel features of construction and arrangement.

of parts that will hereinafter be more fully described and claimed and illustrated in the accompanying drawing in WlllGl1-.-

Fig- 1 is a vertical transverse section taken through the center of one of the power cylinders of my improved engine and through the centers of the 4 pumping and piston Valve cylinders. that are assoclated therewith. v 1 f Fig. 2 is a top plan view of one of the power units of, my improved engine wlth the cylinder head block removed. Fig. 3 is a vertical section taken approxlmately on the linei3.,-3 of Fig, 1.

Referring by numerals to the accompany ing drawing, 10, 1O designate power or combustion cylinders, the chambers within which are connected at their head or inner ends by a common compression and combustion clearance space such as llthat is-formed in the underside: of the cylinder head block 12. One-of these combustion cylinders is providedwith a charge volume inlet port 13 and theother cylinderis provided wlth an ranged so that they are uncovered and open only when the pistons 15 that are arranged igzssai 1 for reciprocatory movement within the COID- bustion chambers in cylinders lOare at the I lower or outer ends of their strokes.

The cylinders lOsurmount a crank case 16 having suitably arranged bearings 17 for a crank shaft 18 and said crankbeing provided with tandem crank pins" such as 19' that are coaxial and which are connected to crank shaft 18 by conventional crankarms 20. These crank arms are provided with suitable counterweights 21,the same being arranged diametrically opposite to the tandem crank pins 19. The'power pistonsv 15 are separately connected to thecranki-pins 19 by suitable connecting rods 22. A

Secured in any suitable manner to crank case 16 and arranged substantially at. right angles or 90 from the axes of cylinders .10 is a charge volume. pumping cylinder 23 within which is arranged for reciprocatory movement a combined piston and counterweight 24. counterweight is connected by a connecting rod 25 to a crank pin'26 that is connected to and disposed between the inner pair of crank arms 21 and said crank pinoccupying the same radial plane with the tandem crank pins 19 but being located nearer to the axis of the crank shaft 18 than the axesof said tandem crank pins. Thus the throw or cir- This combined piston and cularpath of travel ofcrank pin 26 is somethe valve chamber 30 in housing 27 are charge volume inlet ports 31. Leading from Y a suitable source of supply to the annularchamber 29 is a charge Volume supply duct .32. The outer endof cylinder 23 is provided-with a port 33, land leadingtherefrom and communicating with the outer end of piston valve cylinder 27 is a duct 34%. From the outer end of the-pistonwalve cylinder, I

this duct is extended to one of the pair of combustion cylinders that form another power unit of the engine, and-saidduct,

which is designated-by the numeral 35, communicates with the inlet port 13 into the combustion cylinder.

Arran ed; forreciprocatory movement within t e piston valve chamber'3O is a piston valve 36, and arranged between the wrist pin 4:0. of said piston valve, and awrist pin 39 that is seated in a palr of'lugs 37 that are formed on the inner end of connecting rod 25, is a connecting rod 38.

, In the operation of my improved engine,

" a gaseous *fuel charge compressed within common clearance chamber 11 is ignited as the pistons'151 pass high center, and as a result of the rise in pressure following combustion of the compressed fuel charge, the pistonsare forced downward on their power stroke." v v v 7 As the pistonsapproach the lower or outer ends oftheir stroke, the inlet and exhaust valves 13: and 14 respectively are uncovered and opened, and as such action takes place,

a-pllmped charge volume for the pumping cylinder of another one of the engine units entersinlet port 13fromduct and passes upwardly through the corresponding combustion chamber, thence through the common clearance chamber and thence downwardly throughthe combustion chamber having the exhaust port 14, and this incoming charge wdrives. before the burnt gases and products of combustion and which latterescape or discharge through exhaust port 14. On the succeeding upward travel offthe pistons, the

.fuel. charge thus delivered into the combustion chambers is coinpressedin the common clearance-chamber l'lnntil at thepoint of l'ii'ghest compression, said fuel charge is ign-ited'and; thecycle. of operation isrepeated.

Through the connecting rods 22; the reciproeating motion of the power pistons istrans- "mitted to crank shaft 18, and as the latter rotates, the pumping piston 24' and piston valve 36 will be reciprocating in their re 7 spective cylinders.

Inasmuch as the crank and wrist pin 39,

to. which the "crank end of connecting rod 3 38 is connected, is slightly late in rotation and in relation to the dead center line betweenflthe crankshaft, axis and the axis of the piston valve wrist pin 40, the piston valve 36; on its outward stroke will move to a position. to open inlet ports 31 slightly after pumping pistonfla starts on its outward stroke, thus providing the desired lag in opening, so that, as the pistonvalve continuesltomove outwardly, said ports 31 are "opened, thereby admitting a charge volume from duct. 32 and" this charge volume will be drawn through duct 34' and port 33 into the chamber within pumping cylinder 23 in front of the piston 24 therein.

i Y On the inward travel or'stro'keso-f pumppiston and piston. valve 36, the latter will close ports 31 slightly after the pumping piston24; starts on its inward stroke, thus providing the desirable valve closing lag, and as the pumping p ston moves lnward the charge volume previously drawn into the pumping chamber will be forced outwardly through port 33 and thence through 'ducts 34 and 35 to the combustion chambers within the cylinders l0 of another one of the engine power units.

Thus it will be seen that I have provided a twostroke cycle internal combustion engine chambers that are served'by the charge vol ume pump and the parts of the engine being constructed and arranged so as to establish perfect reciprocative force alternation and balance in operation.

changes in the siZe, form and construction of the'various parts of my improved engine may be made and substituted forthoseherein shown and described without departing from the spirit of" the invention, the scope' of which is set forth] in the appended claims. i

I claim as: myfinvention"; I 1". In a twostroke cycle internal combustion. engine, power unit comprising a pair of combustion cylinders, the head ends of which are connected by a common compres- I sion and combustion clearance chamber, pistons arranged for operation withl-nsaid combustion cylinders, a chargevolume pumping cylinder, a'pistonyarranged for reciprocatory movement therein, a piston valve for controlling the admiss onof gaseous fuel into said pumpingcylinder, which piston valve occupies an angular position between the planes OCCIIPlGCl by said combustion cylinders and said charge volume pumping cyl 1nder,.a crank shaft and connections between the pistons inthe combustion cylinders, the

pumpingpiston and the piston valve and said crankshaft. 7

2. In a two stroke cycle internal combustion engine, a power unit comprising a pair of combustion cylinders, the head ends). of which are connected by a common compression and combustion clearance chamber, pis'-' tons arranged} for operation within said combustion cylinders, a charge volume pumping cylinder, a piston arranged for reciprocatory movement therein, a piston valve for cont-rol l ing the admission of gaseous fuel into said pump ng (3yl1I1Clel,"WlllCh piston. valve occupies an angular position betweenthe planes occupiedby said combustion cylinders'andl said charge volume pumping cylinder, a

on It willreadily be understood that vminor crank shaft, connections between the pistons in the combustion cylinders, the pumping piston and the piston valve and said crank shaft, and a charge volume transfer duct arranged between the pumping cylinder and,

the piston valve cylinder, and leading from said piston valve cylinder.

3. In a two stroke cycle internal combustion engine, a power unit comprising a pair of combustion cylinders, the head ends of which are connected by a common compression and combustion clearance chamber, pis tons arranged for operation within said combustion cylinders, a charge volume pumping cylinder, a piston arranged for reciprocatory movement therein, a piston-valve for controlling the admission of gaseous fuel into said pumping cylinder, a crank shaft having tandem crank pins to which the pistonsv in the combustion cylinders are connected, a crank pin forming a part of said crank shaft and arranged between said tandem crank pins, connections from the pumping piston and the piston valve to the intermediate crank pin, the axis of the intermediate crank pin being located at a different distance from the axis of the crank shaft than is the axes of the said tandem crank pins from the axis of the crank shaft and the axes of compression and combustion cylinders being angularly disposed radially with the axis of the crank shaft 90 of the axis of said pumping cylinder.

4. In a two stroke cycle internal combustion engine, a power Lll'llbCOIIlPl'lSlDg a pair of combustion cylinders, the head ends of which are connected by a common compression and combustion clearance chamber, pistons arranged for operation within said combustion cylinders, a charge volume pumping cylinder arranged in a plane substanthere being a radially tandem arrangement of crank pins of the crank shaft to each pair of 90 angularly disposed combustion and pumping cylinders, the axis of the pair of crank pins to which the adjacent pair of combustion cylinder pistons are connected being disposed on a line parallel with the axis of the crank shaft, the piston valve being connected to the crank shaft, the' through a wrist pin held in the crank end of the connectingrod attaching the pump piston to the crank shaft and the position of said crank end wrist pin held in the pump cylinder piston connecting rod, being offset.

late rotatively relative to the line intersecting the crank shaft axis and the axis of the piston end unit pin of the piston valve. 0

5. In a two stroke cycle internal combustion engine, a unit comprising a pair of combustion cylinders, a fresh charge pump cylinder and a piston valve cylinder, piston within each of the four cylinders, a crank shaft having three crank pins to each unit of four cylinders, connection between the four pistons and the three crank pinsof the crank shaft, the two combustion cylinders being adjacent to each other and having axes parallel, the fresh charge pump cylinder be ing radially disposed relative to the pair of adjacent combustion cylinders, with its axis apart from the axes of the combustioncylinders, the piston valve cylinder being angularly disposed in the same radial plane as the combustion and pumpv cylinder and located between the said combustion and pump cylinders, the axes of the combustion cylinders, the pump cylinder and the piston valve cylinders intersecting the axis of the crank shaft, the three crank pins of the crank shaft adapted to each unit of four cylinders being arranged with two pins axially tandem and with a given radial distance between their axes and the axis of the crank shaft, one crank pin between and separating the axially tandem pair of crank pins, the said intermediate crank pin axis being of less radial distance from the axis of the crank shaft, than is the radial distance between the axes of the axially tandem pair of crank pins and the axis of the crank shaft,

a'wrist pin located in the crank end part of the connecting rod that joins. the pump piston to the intermediate crank pin of the least crank throw, the crank end ofthe piston valve connecting rod "being attached to said wrist pin, and the axis of said wrist pin joining the pump piston connecting rod and the piston valve connecting rod, being offset late relative to crank shaft direction of rotation to the dead center line intersecting the axis" of the crank shaft and the axis of the wrist pin in the piston valve towhich the piston end of the piston valve connecting rod is connected.

In, testimony whereof I affix my signature EVERETT R. BURTNETT. 

